【摘要】 <正> 1973年我们在陕西省卫生防疫站所收藏的一大批蚤类标本中,发现一个新属新种,它属于蚤目角叶蚤科,兹记述如下。 巨胸蚤属Megathoracipsylla,新属 此新属较近单蚤属Monopsyllus Kolenati,1857,但有不少属征易于区别。 鉴别特征 主要是前胸背板特长,其长连同前胸栉在内约等于中胸背板(包括颈片),远较窄短的后胸背板为长;无额突,额除眼鬃列和后头除后缘鬃列外,各具1根更多还原

【Abstract】 Megathoracipsylla, gen. nov.Dishag. nosisOnly male known, allied to Monopsyllus Kolenati, 1857, but readily distinguishable by the following characters: (1) pronotum especially long, its length including the pronotal comb equivalent to that of mesonotum including the collar and about 1 1/2 times longer than the metanotum, the collar of which is particularly short; (2) frontal tubercle absent; (3)frontal and occipital rows of bristles vestigial each of which being represented by 1 small bristle; (4) eye small but pigmented, ocular row consisting of 4 bristles; (5) labial palpus 5-segmented reaching slightly beyond apex of fore-trochanter(fig.1) ; (6) basal abdominal sternite with fine striation on the posterior 2/3 of the middle portion) (7) metanotal area water-chestnut shaped; (8) all legs with 5 pairs of lateral plantar bristles in a straight line; (9) Ⅷ ter-gite of male well-developed, but with short bristies on its dorsal margin and without spiculose area on the inner side(fig.3);(10) Ⅷ sternite much reduced and with small membranous flap divided into filaments (fig.4); (11)clasper with a conical and pointed process curving towards the anterior, with broad and short manubrium and with a broad movable process bearing 2 different spiniforms; (12) Ⅸ sternite with a small and slender anterior arm, the shape of which is rather peculiar(fig.2); (13) all tergitcs of thorax and abdomen with main bristle row consisting of slender bristles.Type of the genus M. pentagonia sp. nov. Megathoracipsylla pentagonia, sp. nov.Diagnosis. Pronotum with one row of 6-7 bristles and a pronotal comb of 21 spines on two sides together; metanotum with 2 spinelets which are much smaller than those borne on abdominal tergites; metepimeron with 3 rows of bristles tolal-ling only 4 bristles(fig.1); no bristles on inner sides of mid- and hind-coxae, but 13-15 and 7 bristles are present on their outer sides respectively; fore-femur with A 3 bristles on both the inner and outer sides; no bristles on outer sides of mid-and hind-femora, but about 5 bristles are present on inner side of both mid- and hind-femora; fore-, mid- and hind- tibia with 6, 7, 7 notches respectively, 1 row of 8 - 9 bristles present on the outer side of hind-tibia; proportional ratios of the lengths of Ⅰ-Ⅴ hind-tarsal segments are 6, 4, 2.5, 1.5, 3.5; the longest apcial bristles of Ⅱ hind-tarsal segment reaching to the middie of Ⅳ. Ⅲ-Ⅵ abdominal tergites with 3 rows of bristles (the anterior row being incomplete), and lowest bristle of main bristle row on a level with the spiracle or slightly lower; Ⅰ-Ⅴ tergites with 3, 3, 3, 3, 1 spinelets respectively; Ⅲ-Ⅵ sternites each with 2 rows of bristles 1 and 3-4; 2 antepygidial bristles on each side, the higher one being as long as the distal margin of the movable process; all modified segments including its relative size, shape and chaetotaxy as shown in figs. 2-5.Type data. Holotype (?) measuring 3.2mm. long, collected by the second author in April, 1959 from a forest in Ningshaan-Xian ex Dremomy pernyi. Type deposited in the collection of the Academy of the Military Medical Sciences, Beijing, China.DiscussionThe last part of the paper is a taxonomic discusion on the morphological, host and zoogeographical similarities with its allied genus Monopsyllus. In addition, the elongatod pronotum is also pesent in most genera of Ischnopsyllinae as well as Miocte-nopsylla of Ceratophyllidae, and Minyctenopsylltts and Brachyctenonotus of Lepto-psyllidae. These similarities may be regarded as parallelism occurring in related families & genera. Moreover, the small fixed process of clasper coupled with a big movable process, the large Ⅷ T. and small Ⅷ St. and the small Ⅸ sternate coupled with a well developed aedcagus may be regarded as a case of compensative structure. These are certainly favorable for clasping and copulation. Furthermore, the authors raised a question as to the explanation regarding the reduction of the eye, general charetotaxy of the head, thorax and abdomen. Whether or not this new flea taxa is a nest flea awa更多还原